This disclosure generally relates to a method of fabricating an airfoil and a core assembly for defining features within a completed airfoil.
A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high-speed exhaust gas flow. The high-speed exhaust gas flow expands through the turbine section to drive the compressor and the fan section. The compressor section typically includes low and high pressure compressors, and the turbine section includes low and high pressure turbines.
Airfoils for vanes and blades in the turbine section are exposed to high temperature, high-speed exhaust gas flow. A stream of cooling airflow is therefore often provided along exposed surfaces. Cooling channels within the airfoil communicate cooling air to openings to generate the desired cooling airflow. Airfoils are typically molded parts and the internal cavities and passages required to communicate cooling airflow are provided by core assemblies over-molded during a molding process.
Core assemblies define the interior passages and channels within the airfoil and therefore improved core configurations that improve the molding process and improve performance are desirable.